V70R AWD L5-2.3L Turbo VIN 52 B5234T6 (1998)
Vacuum Pump: Description and Operation
Vacuum Pump And Regulator
The vacuum pump with built-in regulator is located in the engine compartment.
The vacuum pump is driven by an electric motor controlled by a relay, activated by the control module when all conditions are met. The vacuum
pump adjusts the vacuum in the vacuum servo to correspond to the programmed speed. Current speed is monitored by the speedometer, which
sends a constant signal to the control module.
When an increased throttle opening is required, for example when driving uphill, the vacuum pump will supply the regulator with more vacuum
until the programmed speed is reached. When driving downhill, on the other hand, the regulator will open its release valve to reduce the vacuum
and decrease the throttle opening.
